R help - Oct 2009 - R neophyte question.

Hi all,

I'm currently working through the "Beginner's Guide to R"
(Zurr et al.) and
I'm wondering about the first exercise in chapter 3:

I imported the data from BirdFluCases.txt and executed the 'names' and
'str'
functions as follows:

Bird = read.table(file='C:\\rbook\\BirdFluCases2.txt', header=TRUE)
names(Bird)

[1] "Year"       "Azerbaijan" "Bangladesh"
"Cambodia"   "China"
"Djibouti"   "Egypt"
 [8] "Indonesia"  "Iraq"       "LaoPDR"    
"Myanmar"    "Nigeria"
"Pakistan"   "Thailand"
[15] "Turkey"     "VietNam"

str(Bird)

'data.frame':   6 obs. of  16 variables:
 $ Year      : int  2003 2004 2005 2006 2007 2008
 $ Azerbaijan: int  0 0 0 8 0 0
 $ Bangladesh: int  0 0 0 0 0 1
 $ Cambodia  : int  0 0 4 2 1 0
 $ China     : int  1 0 8 13 5 3
 $ Djibouti  : int  0 0 0 1 0 0
 $ Egypt     : int  0 0 0 18 25 7
 $ Indonesia : int  0 0 20 55 42 18
 $ Iraq      : int  0 0 0 3 0 0
 $ LaoPDR    : int  0 0 0 0 2 0
 $ Myanmar   : int  0 0 0 0 1 0
 $ Nigeria   : int  0 0 0 0 1 0
 $ Pakistan  : int  0 0 0 0 3 0
 $ Thailand  : int  0 17 5 3 0 0
 $ Turkey    : int  0 0 0 12 0 0
 $ VietNam   : int  3 29 61 0 8 5

I obtained the total number of bird flu cases in 2003 and 2005 respectively
with:

sum(Bird[1,2:16])

[1] 4

and

sum(Bird[3, 2:16])

[1] 98


I don't know how to obtain the answers for 'Which country has had the
most
cases?', 'Which country has had the least bird flu deaths?' or
(using
methods from chapter 2), 'What is the total number of bird flu cases per
country?' and 'What is the total number of cases per year?'

The rowSums and colSums functions haven't been introduced at this point in
the text.

Thanks,

Katie

	[[alternative HTML version deleted]]

Katie Miller <bioprogrammer <at> gmail.com> writes:
> 
> Hi all,
> 
> I'm currently working through the "Beginner's Guide to R"
(Zurr et al.) and
> I'm wondering about the first exercise in chapter 3:
> 
 [snip]
> I don't know how to obtain the answers for 'Which country has had
the most
> cases?', 'Which country has had the least bird flu deaths?' or
(using
> methods from chapter 2), 'What is the total number of bird flu cases
per
> country?' and 'What is the total number of cases per year?'
> 
> The rowSums and colSums functions haven't been introduced at this point
in
> the text.

   Can you assure us this isn't a homework assignment?

 The authors have introduced matrix indexing, so what about sum(Bird[,2]),
sum(Bird[,3]), ... [or apply(Bird[,-1],2,sum)?]